Usually organic farms are GMO free since they are not allowed to use pesticides (which are what GMO's are made to tolerate without dying.) Hobbyists that have little farm stands also tend to be GMO free as they're not trying to produce huge crops, just enough for themselves and maybe a little extra for sale. Of course if you are near a farm you can always ask! Also anything labelled "heirloom" or "heritage" is GMO free just by it's nature. It basically means it's a form of plant that is ancestral, something that was first bred and produced at least several generations before we were born. Hope this helps, good luck!